In recent years, there have been mobile information terminals (hereinafter, abbreviated as terminals), such as smartphones and tablets, in which a display unit has a narrow frame or does not have a frame. There also have been terminals in which a housing has a frame with a narrow width.
Each of the terminals as described above has an advantage that a region of a display unit as an interface is wide. As another advantage, it is possible to detect a touch on an end portion (edge) of the terminal and provide an operation according to the touch.
For example, PTL 1 describes a mobile terminal apparatus that determines a manner of holding the mobile terminal apparatus on the basis of the number of touch regions which are regions where touches are detected by touch sensors and areas of the touch regions, and generates a display picture suitable for the holding manner.
However, when a user holds the terminal so as to grip it with his/her hand, the hand holding the terminal is in contact with an end portion of the terminal. The terminal may recognize such contact with the end portion of the terminal by the holding hand as a touch operation and execute an operation that is not intended by the user. Thus, a terminal that invalidates (that is, does not receive as a touch operation) contact with the end portion by the hand holding the terminal has been developed.
For example, a terminal apparatus described in PTL 2 acquires touch information, which is information about positions of touches and the number of touches, from touch sensors arranged on sides of a housing, and determines a holding hand on the basis of the acquired touch information. Then, on the basis of a result of the determination for the holding hand, the terminal apparatus determines a touch detected at either right or left (or upper or lower) end portion as contact by the holding hand, and invalidates the touch.